let create
  ?(starting_timeout=5.) ?(call_script=fun s -> [default_shell; s])
  ?(using=`Nohup_setsid) ?(host=Ketrew_host.tmp_on_localhost)
  ?(no_log_is_ok=false)
  program =
  let shell_command = call_script script_placeholder in
  let c =
    {host; program; using; starting_timeout; shell_command; no_log_is_ok } in
  `Long_running (name, `Created c |> serialize)